org.cloudgraph.store.mapping.codec

Interface KeyFieldCodec

All Known Implementing Classes:

HashKeyFieldCodec, LexicoHashKeyFieldCodec, LexicoPadKeyFieldCodec, LexicoSimpleKeyFieldCodec, NativeKeyFieldCodec

public interface KeyFieldCodec

Implementations are responsible for converting composite row key field, actual as well as user supplied literal, query values to and from byte representations. Bridges the key field creation activity using actual data objects, and the querying of key fields using only meta data describing them.

Since:

1.1.0

Author:

Scott Cinnamond

Method Summary

Modifier and Type	Method and Description
boolean	checkEncodeOverflow(byte[] keyValue) Returns true if the given encoded value will overflow the underlying key field.
Object	decode(byte[] value) Returns the object representation for the given encoded bytes value.
byte[]	encode(Object value) Returns the encoded bytes representation for the given object or literal value.
byte[]	encodeNext(Object value) Returns the encoded "next" bytes representation for the given object or literal value, where the next value depends on the coded implementation and may typically be the lexicographic next value.
boolean	isLexicographic() Return true if the encoded values support lexicographic ordering.
boolean	isTransforming() Return true if the encoded values are fundamentally transformed father than formatted or padded in some way.

Method Detail

isLexicographic

boolean isLexicographic()

Return true if the encoded values support lexicographic ordering. For example integer values are not encoded natively but as the integer string representation.

Returns:

true if the encoded values support lexicographic ordering

isTransforming

boolean isTransforming()

Return true if the encoded values are fundamentally transformed father than formatted or padded in some way.

Returns:

true if the encoded values are fundamentally transformed father than formatted or padded in some way.

checkEncodeOverflow

boolean checkEncodeOverflow(byte[] keyValue)

Returns true if the given encoded value will overflow the underlying key field.

Parameters:

keyValue -

Returns:

true if the given encoded value will overflow the underlying key field.

encode

byte[] encode(Object value)

Returns the encoded bytes representation for the given object or literal value.

Parameters:

value - the object or literal value

Returns:

the encoded bytes representation

Throws:

KeyFieldOverflowException - if the encoded data exceeds the capacity of the target field

decode

Object decode(byte[] value)

Returns the object representation for the given encoded bytes value.

Parameters:

value - encoded bytes value

Returns:

the object representation for the given encoded bytes value

encodeNext

byte[] encodeNext(Object value)

Returns the encoded "next" bytes representation for the given object or literal value, where the next value depends on the coded implementation and may typically be the lexicographic next value.

Parameters:

value - the object or literal value

Returns:

the encoded bytes representation

Throws:

KeyFieldOverflowException - if the encoded data exceeds the capacity of the target field